Choline is necessary for the normal functioning of the mammalian organism. Hepatic steatosis associated with the use of total parenteral nutrition (TPN) is caused by choline deficiency. The aim of this study is to confirm that choline-supplemented TPN causes a decrease or resolution of hepatic steatosis in long term TPN patients with choline deficiency manifested by hepatic steatosis, and to determine whether recurrence can be prevented by continued choline supplemen-tation. Subjects will be randomized to receive choline in their TPN or placebo (no choline).